CN103201878A - Non-aqueous electrolyte secondary battery - Google Patents

Non-aqueous electrolyte secondary battery Download PDF

Info

Publication number
CN103201878A
CN103201878A CN201080068629XA CN201080068629A CN103201878A CN 103201878 A CN103201878 A CN 103201878A CN 201080068629X A CN201080068629X A CN 201080068629XA CN 201080068629 A CN201080068629 A CN 201080068629A CN 103201878 A CN103201878 A CN 103201878A
Authority
CN
China
Prior art keywords
porous layer
circularity
secondary battery
electrolytic solution
nonaqueous electrolytic
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN201080068629XA
Other languages
Chinese (zh)
Other versions
CN103201878B (en
Inventor
上木智善
岛村治成
福本友祐
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toyota Motor Corp
Original Assignee
Toyota Motor Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toyota Motor Corp filed Critical Toyota Motor Corp
Publication of CN103201878A publication Critical patent/CN103201878A/en
Application granted granted Critical
Publication of CN103201878B publication Critical patent/CN103201878B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624—Electric conductive fillers
    • H01M4/626—Metals
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/058—Construction or manufacture
    • H01M10/0587—Construction or manufacture of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/431—Inorganic material
    • H01M50/434—Ceramics
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
    • H01M50/491—Porosity
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Abstract

The disclosed non-aqueous electrolyte secondary battery is provided with an electrode body formed by superimposing a positive electrode sheet and a negative electrode sheet (20) separated by a separator sheet (40), wherein between the separator sheet (40) and the positive electrode sheet and/or the negative electrode sheet (20), a porous layer (42) is formed having filler particles (44) and a binder, and the median value in the circularity distribution of the filler particles (44) contained in the porous layer (42) is 0.85-0.97.

Description

Nonaqueous electrolytic solution secondary battery
Technical field
The present invention relates to nonaqueous electrolytic solution secondary battery, at length say, relate to the nonaqueous electrolytic solution secondary battery that between at least one side of separator sheets and positive plate and negative plate, is formed with porous layer.
Background technology
In recent years, the nonaqueous electrolytic solution secondary battery of lithium ion battery, Ni-MH battery etc. improves as vehicle boarded its importance of power supply with power supply or personal computer and portable terminal device.Particularly in light weight and can obtain the lithium ion battery of high-energy-density, expect as can be well as the battery of vehicle boarded usefulness high-output power power supply.In a typical case of this lithium secondary battery constitutes, as the dividing plate between positive pole and negative pole, use the multiple aperture plasma membrane of polyolefin.
But the multiple aperture plasma membrane of polyolefin is plastic, thus when reaching a high temperature in the battery easy deformation, the risk raising that internal short-circuit (short) waits takes place.Therefore, one of means that produce as the unfavorable condition that prevents short circuit generation etc. more effectively, any one the surface of for example having discussed among anodal, negative pole or dividing plate forms the thermal endurance porous layer (for example patent documentation 1) that is made of inorganic filler.Constitute according to this, even dividing plate has taken place under the situation of distortion, also can utilize the thermal endurance porous layer to prevent contacting of positive pole and negative pole, can suppress short circuit and take place.
Technical literature formerly
Patent documentation 1: the open 2008-305783 communique of Japan's patent application
Summary of the invention
Once disclosed a kind of lithium secondary battery in patent documentation 1, its surface at the 1st carrier ring has formed has the 2nd carrier ring (porous layer) that heat resisting temperature is the filler more than 150 ℃.According to this communique, the filler that constitutes the thermal endurance porous layer is preferably tabular particle, as its representational filler, illustration plate-like aluminum oxide and tabular boehmite.But if use so tabular particle to form the thermal endurance porous layer, then because the pressure that shrinks with the expansion that discharges and recharges electrode together, porous layer crumbles, and the porosity of porous layer reduces.If the porosity of porous layer reduces, then electrolyte and ion can not pass through in porous layer, use the performance (part throttle characteristics and two-forty durability) of the lithium secondary battery of this porous layer structure to become insufficient, and be therefore not preferred.
The present invention finishes in view of this, and its main purpose provides a kind of nonaqueous electrolytic solution secondary battery that has suppressed to be reduced by the porosity of porous layer the performance degradation that causes.
Nonaqueous electrolytic solution secondary battery provided by the invention is the lithium secondary battery that possesses electrode body, and described electrode body is that positive plate and negative plate overlap the electrode body that forms across separator sheets.Between at least one side and aforementioned barriers sheet of above-mentioned positive plate and above-mentioned negative plate, be formed with the porous layer with filler grain and adhesive.Intermediate value during the circularity of the filler grain that contains in the above-mentioned porous layer distributes is 0.85～0.97.
The circularity of above-mentioned filler grain for example can be calculated girth and area by projection image's (particle picture) of filler grain, tries to achieve by following formula (1).
Circularity a=L0/L1 (1)
At this, L0 in the above-mentioned formula (1) be have with by practical measurement the girth of ideal circle (just round) of the area area identical calculated of projection image's (particle picture) of object particle, L1 is the girth of the reality that determines of the particle projection image (particle picture) by this determination object particle.
That is, the circularity that becomes the powder of determination object distributes (being typically number distributes), is to try to achieve by measuring the circularity of being calculated by above-mentioned formula (1) for each filler grain that constitutes this powder.This circularity distributes can be by for example commercially available particle picture analytical equipment, for example mobile particle image analytical equipment is easily measured.
Intermediate value in distributing as the circularity of the filler grain that is obtained by above-mentioned particle image analytical equipment, it is 0.85～0.97 more suitable to be about.If the intermediate value that circularity distributes is greater than 0.97, then filler grain becomes more close to spherical, so the fillibility of filler grain improves, the high porosityization of the porous layer difficulty that becomes.In addition, flow easily because filler grain becomes when being filled by height, therefore be subjected to the pressure that shrinks with the expansion that discharges and recharges electrode together, porous layer is compressed, and the circulation deterioration takes place sometimes.On the other hand, if the intermediate value that circularity distributes less than 0.85, though then can improve the porosity of porous layer, the amount of filler that contains in the unit volume of porous layer reduces, and therefore can not get preventing the anodal effect that contacts with negative pole sometimes.In addition, because the intensity of porous layer is often not enough, therefore be subjected to the pressure that shrinks with the expansion that discharges and recharges electrode together, porous layer crumbles, and the circulation deterioration takes place sometimes.
Therefore, it is 0.85～0.97 more suitable that the intermediate value during the circularity of the filler grain that contains in the porous layer distributes is about, and is preferably 0.85～0.96, and more preferably 0.85～0.93, be preferably 0.85～0.9 especially.If in the scope that such circularity distributes, then can access the amount of filler that contains in the unit volume of suitably keeping porous layer, and have electrolyte permeability and the high porous layer of mechanical strength as porous layer appropriate porosity (for example 50～70%, be preferably 56～70%, be preferably 60～70% especially).If use such porous layer, then can make up safe and the good nonaqueous electrolytic solution secondary battery of battery behavior (part throttle characteristics and two-forty durability).
In one mode of preferred nonaqueous electrolytic solution secondary battery disclosed herein, during the circularity of the filler grain that contains in above-mentioned porous layer distributes, with be 0.7～0.9 from the suitable circularity value of the accumulation 10% of the little side of circularity (below, be called value (lower value) down).Distribute if be set at such circularity, then contain unsetting with certain proportion and the particle of corner angle is arranged, therefore by this particle of corner angle is arranged, suppress the slip between filler grain, the fillibility of filler moderately reduces.Therefore, can stably obtain as described above have the porous layer of the best of high mechanical strength and excellent electrolyte permeability concurrently with high level.
In one mode of preferred nonaqueous electrolytic solution secondary battery disclosed herein, above-mentioned filler grain is aluminium oxide or hydrated alumina.Aluminium oxide or hydrated alumina distribute preferred aspect being easier to adjusting circularity by the processing of pulverizing etc.In addition, aluminium oxide or hydrated alumina since Mohs' hardness than higher, therefore preferred aspect the mechanical strength that can improve porous layer and durability.
In one mode of preferred nonaqueous electrolytic solution secondary battery disclosed herein, above-mentioned porous layer is formed at the surface of aforementioned barriers sheet.Under this situation, it is cheap that manufacturing cost becomes, and can battery performance not made a very bad impression and form porous layer between separator sheets and electrode slice.Preferred above-mentioned porous layer for example is formed on the face relative with negative plate of aforementioned barriers sheet.
In one mode of preferred nonaqueous electrolytic solution secondary battery disclosed herein, above-mentioned electrode body is the rolled electrode body that above-mentioned positive plate and above-mentioned negative plate are reeled and formed across the aforementioned barriers sheet.Be under the situation of rolled electrode body in above-mentioned electrode body, take place especially easily to reduce the performance degradation that causes by the porosity of porous layer that it is particularly useful therefore to use the present invention.
Any nonaqueous electrolytic solution secondary battery disclosed herein possesses the performance (for example can obtain high-output power), the particularly excellent in te pins of durability that discharges and recharges for two-forty that are suitable as the battery that vehicle carries.Therefore according to the present invention, can provide the vehicle that possesses any nonaqueous electrolytic solution secondary battery disclosed herein.Particularly can provide and possess this nonaqueous electrolytic solution secondary battery as the vehicle (for example automobile) of power source (being typically the power source of motor vehicle driven by mixed power or motor vehicle).
Description of drawings
Fig. 1 is the side view that the nonaqueous electrolytic solution secondary battery that one embodiment of the present invention relates to is represented on pattern ground.
Fig. 2 is II-II line sectional view of Fig. 1.
Fig. 3 is the figure that the electrode body of the nonaqueous electrolytic solution secondary battery that one embodiment of the present invention relates to is represented on pattern ground.
Fig. 4 is the amplification sectional view of the major part of the nonaqueous electrolytic solution secondary battery that relates to of expression one embodiment of the present invention.
Fig. 5 is the figure for the assay method of the routine film resistor that relates to of explanation one test.
Fig. 6 is the side view that pattern ground expression possesses the vehicle of the nonaqueous electrolytic solution secondary battery that one embodiment of the present invention relates to.
Embodiment
Below, on one side with reference to accompanying drawing, embodiments of the present invention are described on one side.In following accompanying drawing, the subsidiary same tag of member and position to the performance same function describes sometimes.Moreover the size relationship among each figure (length, width, thickness etc.) does not reflect actual size relationship.In addition, beyond the item of mentioning especially in this manual, the necessary item of enforcement of the present invention (for example, possess general technology that the structure of the battery of the formation of electrode body of anodal and negative pole and method for making, dividing plate and electrolytical formation and method for making, nonaqueous electrolytic solution secondary battery etc. relates to etc.), can be used as based on the technical staff's of the prior art in this field design item and grasp.
Limit though be that intention is special, following Lithium Secondary Battery Of Nonaqueous Electrolyte (lithium ion battery) with the form of having accommodated the electrode body (rolled electrode body) that is wound and nonaqueous electrolytic solution in the container of cylinder type is that example explains the present invention.
The summary formation of the lithium ion battery that one embodiment of the present invention relates to is shown in Fig. 1～3.This lithium ion battery 100 has following formation: the electrode body (rolled electrode body) 80 of the form that the negative plate 20 of the positive plate 10 of long shape and long shape is wound across the dividing plate 40 of long shape together is accommodated in the container 50 of the shape (cylinder type) that can accommodate this rolled electrode body 80 with not shown nonaqueous electrolytic solution.
Container 50 possesses the lid 54 of the open container body that the round-ended cylinder shape is arranged in upper end 52 and inaccessible its peristome.As the material that constitutes container 50, can preferably use the stainless steel of aluminium, steel, nickel plating SUS(nickel plating) etc. metal material (being nickel plating SUS in the present embodiment).Perhaps, also can be with the resin material of polyphenylene sulfide (PPS), polyimide resin etc. the container 50 that (moulding) form that is shaped.(being lid 54) is provided with the positive terminal 70 that is electrically connected with the positive pole 10 of rolled electrode body 80 on container 50.Below container 50, be provided with the negative terminal 72(that is electrically connected with the negative pole 20 of rolled electrode body 80 in this embodiment container body 52 double as be it).Rolled electrode body 80 and not shown nonaqueous electrolytic solution together are housed in the inside of container 50.
The rolled electrode body 80 that present embodiment relates to, same with the rolled electrode body of common lithium ion battery except the formation of dividing plate 40 described later, as shown in Figure 3, the stage before assembling rolled electrode body 80 has the chip architecture of long shape (band shape).
Positive plate 10, the two sides at the positive electrode collector 12 of paper tinsel shape with lengthy motion picture shape maintains the structure of the positive electrode active material layer 14 that contains positive active material.But, positive electrode active material layer 14, non-cohesive at the lateral margin (being the side edge portions of downside among the figure) along the horizontal end limit of positive plate 10, be formed with the non-forming portion of positive electrode active material layer that positive electrode collector 12 is exposed with certain width.
The two sides at the negative electrode collector 22 of paper tinsel shape that negative plate 20 also similarly has a lengthy motion picture shape with positive plate 10 maintains the structure of the negative electrode active material layer 24 that contains negative electrode active material.But, negative electrode active material layer 24, non-cohesive at the lateral margin (being the side edge portions of upside among the figure) along the horizontal end limit of negative plate 20, be formed with the non-forming portion of negative electrode active material layer that negative electrode collector 22 is exposed with certain width.
When making rolled electrode body 80, as shown in Figure 3, positive plate 10 and negative plate 20 are stacked across separator sheets 40.At this moment, in the non-non-mode of partly stretching out respectively from the horizontal both sides of separator sheets 40 that forms of negative electrode active material layer that forms part and negative plate 20 of the positive electrode active material layer of positive plate 10, this positive plate 10 and negative plate 20 are laterally slightly being overlapped with staggering.The laminated body that has overlapped like this by reeling can be produced rolled electrode body 80.
Middle body on the wireline reel direction of rolled electrode body 80 forms the negative electrode active material layer 24 of positive electrode active material layer 14 that coiling core segment 82(is positive plate 10, negative plate 20 and separator sheets 40 by closely stacked part).In addition, at the axial both ends of the coiling of rolled electrode body 80, the non-formation of the electrode active material layer of positive plate 10 and negative plate 20 part is stretched out to the outside from coiling core segment 82 respectively.On this side of the positive electrode extension (being the non-formation part of positive electrode active material layer 14) 84 and negative side extension (being the non-formation part of negative electrode active material layer 24) 86, positive wire terminal 74 and negative wire terminal 76 have been set up respectively, with above-mentioned positive terminal 70 and negative terminal 72(at this, container body 52 double as are it) be electrically connected respectively.
Constitute the inscape of this rolled electrode body 80, except separator sheets 40, can be same with the rolled electrode body of in the past lithium ion battery, be not particularly limited.For example, positive plate 10, can give with the lithium ion battery positive active material at the positive electrode collector 12 of long shape is that the positive electrode active material layer 14 of principal component forms.Positive electrode collector 12 can preferably use the anodal metal forming that is suitable for of aluminium foil etc.As positive active material, can be not particularly limited to use from one or more of material that just were used in the lithium ion battery in the past.As the preferred application of technology disclosed herein, can enumerate with lithium manganese oxide (LiMn 2O 4), lithium and cobalt oxides (LiCoO 2), lithium nickel oxide (LiNiO 2) wait, contain lithium and transition metal and be the positive active material of principal component as the oxide (lithium transition-metal oxide) that constitutes metallic element.
Negative plate 20, can give with the lithium ion battery negative electrode active material at the negative electrode collector 22 of long shape is that the negative electrode active material layer 24 of principal component forms.Negative electrode collector 22 can preferably use the metal forming that is suitable for negative pole of Copper Foil etc.Negative electrode active material can be not particularly limited to use from one or more of material that just were used in the lithium ion battery in the past.As being fit to example, can enumerate carbon-based material, lithium-containing transition metal oxide and the transition metal nitride etc. of graphitic carbon, amorphous carbon etc.
The separator sheets 40 that present embodiment relates to has most pores in the inside of this dividing plate, and by the connection of this pore, nonaqueous electrolytic solution and lithium ion can pass through in the inside of separator sheets.In addition, separator sheets 40, owing to overcharge etc. under the situation of abnormal heating, pore obturation (shut down) is cut off electrically contacting between both positive and negative polarity at battery.
As the porous matter resin that constitutes this separator sheets, can enumerate for example porous matter polyolefin-based resins.As being fit to example, can enumerate the resin of three-decker of single layer structure, polypropylene (PP)/polyethylene (the PE)/polypropylene (PP) of porous matter polyethylene (PE).
In addition, between at least one side of separator sheets 40 and positive plate 10 and negative plate 20, be formed with porous layer 42.In this embodiment, porous layer 42 be formed at separator sheets 40, with negative plate 20 facing surfaces on.
And then, adding Fig. 4, the porous layer 42 that relates to for present embodiment explains.Fig. 4 is the pattern sectional view that the part along the cross section of wireline reel of rolled electrode body 80 is represented enlargedly, the figure of the porous layer 42 that show separator sheets 40, forms on the surface of this separator sheets 40 and the negative plate 20 relative with this porous layer 42.
The porous layer 42 that present embodiment relates to as shown in Figure 4, is made of filler grain 44 and not shown adhesive, between filler grain, between filler grain and the separator sheets by adhesives.Porous layer is at the pore 48 that is not had majority by the position of adhesives, and by the connection of this pore 48, electrolyte and ion can pass through in porous layer.In addition, porous layer 42, have the thermal endurance in the infusible degree of the temperature province higher than the fusing point of separator sheets 40 (for example more than 150 ℃), also can utilize porous layer 42 to avoid electrically contacting of anodal and negative pole even taken place in battery adstante febre separator sheets under the situation of distortion.
The porosity of above-mentioned porous layer 42, usually preferably set electrolyte and ion permeability good more than 50% (for example 50～70%), for example more than 52% the scope of (for example 52～70%) is more suitable, more preferably more than 56% (for example 56～70%) is preferably more than 60% (for example 60～70%) especially.If in the scope of the porosity of such porous layer, then the electrolyte of porous layer and ion permeability are abundant, battery behavior (part throttle characteristics, cycle characteristics) is improved.
In addition, this thickness can be selected suitable thickness according to purposes, but in order to be prevented the anodal effect that contacts with negative pole effectively, it is more suitable to be about 1 μ m～20 μ m, is preferably 2～10 μ m, and more preferably 3～6 μ m are preferably 3～5 μ m especially.
As the filler grain that constitutes this porous layer, preferred: have thermal endurance (for example more than 150 ℃), and in the scope of application of battery the filler grain of electrochemical stability.As such inorganic filler, can enumerate the filler grain that is constituted by inorganic metal compound.Routine as being fit to, but illustration aluminium oxide (Al 2O 3), hydrated alumina (boehmite (Al for example 2O 3H 2O)), magnesium hydroxide (Mg(OH) 2), magnesium carbonate (MgCO 3) inorganic metal compound that waits.Can use one or more of these inorganic metal compound materials.Wherein, aluminium oxide or hydrated alumina distribute preferred aspect being easier to adjusting circularity by the processing of pulverizing etc.The particle diameter of this filler grain, for example the D50 diameter based on the laser diffraction and scattering method has no particular limits, but under the situation of for example using aluminium oxide, preferably is about in the scope of 0.2 μ m～1.2 μ m.In addition, under the situation of using boehmite, preferably be about in the scope of 0.4 μ m～1.8 μ m.In addition, the specific area based on the BET method of this filler grain under the situation of for example using aluminium oxide, preferably is about 1.3m 2/ g～18m 2In the scope of/g.In addition, under the situation of using boehmite, preferably be about 2.8m 2/ g～27m 2In the scope of/g.
In addition, as the hydrated alumina that except boehmite, also can obtain same effect, but illustration pseudobochmite (pseudo boehmite), θ-aluminium oxide (about 900 ℃), δ-aluminium oxide (about 800 ℃), κ-aluminium oxide (about 800 ℃), gama-alumina (about 500 ℃), χ-aluminium oxide (about 500 ℃), η-aluminium oxide (about 500 ℃), false gama-alumina (about 500 ℃), ρ-aluminium oxide (about 250 ℃) etc.Moreover, the suitable firing temperature during the synthetic above-mentioned hydrated alumina of the numeric representation in the above-mentioned bracket.Moreover, be typically the H of these hydrated aluminas (can be non-hydrate) 2O/Al 2O 3Mol ratio, pseudobochmite can be 2:1, and other hydrated alumina can be in 0～1 the scope.
As the shape of this filler grain, can take from close to tabular shape to the different shape that approaches with spherical shape, but in the present embodiment, the intermediate value during the circularity of filler grain distributes is 0.85～0.97.If the intermediate value that circularity distributes is greater than 0.97, then filler grain becomes more approaching and spherical shape, so the raising of the fillibility of filler grain, and it is difficult that the high porosityization of porous layer becomes.In addition, when filler grain is filled by height, become and flow easily, therefore be subjected to the pressure that shrinks with the expansion that discharges and recharges electrode together, the circulation deterioration takes place in porous layer compressed (rolling) sometimes.On the other hand, if the intermediate value that circularity distributes less than 0.85, though then can improve the porosity of porous layer, the amount of filler that contains in the unit volume of porous layer reduces, and therefore can not get preventing the anodal effect that contacts with negative pole sometimes.In addition, because the intensity of porous layer becomes often not enough, therefore be subjected to the pressure that shrinks with the expansion that discharges and recharges electrode together, porous layer crumbles, and the circulation deterioration takes place sometimes.
Therefore, intermediate value during the circularity of the filler grain that contains in the porous layer distributes is about 0.85～0.97(for example 0.9～0.97) more suitable, be preferably 0.85～0.96(for example 0.91～0.96), more preferably 0.85～0.93, be preferably 0.85～0.9 especially.If in the scope that such circularity distributes, then can access the amount of filler that contains in the unit volume of suitably keeping porous layer, and have electrolyte permeability and the high porous layer of mechanical strength as porous layer appropriate porosity (for example 50～70%, be preferably 56～70%, be preferably 60～70% especially).If use such porous layer, then can make up safe and the good Lithium Secondary Battery Of Nonaqueous Electrolyte of battery behavior (part throttle characteristics and two-forty durability).
In addition, preferred: as during the circularity of the filler grain that contains in porous layer distributes, and to be 0.7～0.9 from the suitable circularity value of the accumulation 10% of the little side of circularity (below, be called value down).If the following value that circularity distributes is greater than 0.9, then most particle becomes close to spherical shape, and therefore by further high the filling, the porosity of porous layer significantly reduces.Relative therewith, if the following value that circularity is distributed is set at 0.7～0.9, then contain unsetting with certain proportion (total number about 10%) and the particle of corner angle is arranged, therefore have the particle of corner angle to suppress interparticle slip by this, the fillibility of filler moderately reduces.Therefore, can stably obtain as described above have the porous layer of the best of high mechanical strength and excellent electrolyte permeability concurrently with high level.
In addition, if the following value that circularity distributes less than 0.7, then the porosity of porous layer further improves, but the amount of filler that contains in the unit volume of porous layer reduces, and therefore can not get preventing the anodal effect that contacts with negative pole sometimes.Therefore, it is 0.7～0.9 more suitable that the following value that circularity distributes is about, and is preferably 0.73～0.88, and more preferably 0.75～0.85, be preferably 0.78～0.82 especially.If in this scope, then can access the amount of filler that contains in the unit volume of suitably keeping porous layer, and have the porous layer of the best of high mechanical strength and good ion permeability concurrently.
Employed adhesive in this porous layer is the material that bonds between above-mentioned filler grain be used to making, and the material itself that constitutes this adhesive does not limit especially and can use various adhesives widely.As being fit to example, can enumerate acrylic resin.As acrylic resin, can preferably use monomer with acrylic acid, methacrylic acid, acrylamide, Methacrylamide, 2-Hydroxy ethyl acrylate, methacrylic acid-2-hydroxy methacrylate, methacrylate, methyl methacrylate, EHA, butyl acrylate etc. with a kind of homopolymers that is polymerized.In addition, acrylic resin also can be the copolymer that two or more above-mentioned monomer polymerizations is formed.In addition, also can be two or more materials that mix with above-mentioned homopolymers and copolymer.Except above-mentioned acrylic resin, also can use polyvinylidene fluoride, polytetrafluoroethylene (PTFE), polyacrylonitrile, polymethyl methacrylate etc.
Moreover though do not limit especially, preferred filler particle shared ratio in porous layer integral body is about more than the 90 quality % and (is typically 95 quality %～99 quality %), preferably is about 96 quality %～99 quality %.In addition, the ratio of the adhesive in the porous layer is preferably set to below about 5 quality %, more preferably is set at about 4.9 quality % following (for example about 0.5 quality %～3 quality %).In addition, containing under the situation that porous layer beyond filler grain and the adhesive forms composition (for example tackifier etc.), the total of preferred these optional members contains proportional being set at below about 3 quality %, more preferably is set at about 2 quality % following (for example about 0.5 quality %～1 quality %).
Then, the formation method for above-mentioned porous layer describes.This porous layer formation method comprises:
(A) preparation is as the metal compound powders (can buy commercially available metal compound powders, also can oneself synthesize) of filler grain;
(B) above-mentioned metal compound powders is carried out pulverization process or spheroidizing processing, so that the intermediate value in the distribution of the circularity of the metal compound powders of above-mentioned preparation becomes 0.85～0.97; With
(C) after above-mentioned pulverization process or spheroidizing are handled, be modulated at the porous layer formation coating that has disperseed above-mentioned metal compound powders and adhesive in the solvent, with its be applied among positive plate, negative plate and the separator sheets at least any one the surface and carry out drying, form porous layer thus.
In the operation of the preparation metal compound powders in above-mentioned (A), prepare employed metal compound powders in the porous layer.This metal compound powders is synthetic by the starting compound powder of regulation, for example, the powder of the starting compound (being initiation material) of a part that can be by preparing to contain the metallic element that constitutes this metal compound powders, and this starting compound burnt till to synthesize.Perhaps, the powder of the starting compound (being initiation material) of a part that can be by will containing the metallic element that constitutes this metal compound powders dissolves in appropriate solvent or disperses and keep in thermostat, with the reaction product that obtains filter, washing, dry come synthetic.Perhaps, also can buy commercially available metal compound powders (existing finished product) uses.
For example, under the situation of Borolon powder, preferably: prepare to contain the powder of the starting compound (for example aluminium hydroxide) of the metallic element (Al) that constitutes this alumina powder, with this starting compound powder in atmosphere or oxygen than burning till in the rich oxygen atmosphere of atmosphere.Be crushed to by the burned material that will obtain and become suitable size (particle diameter), obtain desirable alumina powder.As the above-mentioned firing temperature that burns till in the processing, as long as for the above-mentioned raw materials compound becomes the temperature province that the reaction of aluminium oxide can be carried out, it is more suitable to burn till at (for example 1000～1200 ℃, for example 1150 ℃ ± 50 ℃) more than 1000 ℃ usually.In addition, become the time that the sufficient reacting ground of aluminium oxide carries out as long as firing time is set at up to the above-mentioned raw materials compound, it is just enough to be set at more than 90 hours (for example 90～120 hours, for example about 96 hours) usually.By burning till under such condition, aluminium oxide particles is grown greatlyyer, therefore becomes to handle to adjust the circularity distribution of alumina powder easily by pulverization process described later or spheroidizing.
In addition, boehmite powder can be synthetic by hydro thermal method.For example, preferred: as to prepare to contain the powder of the starting compound (for example alumina trihydrate) of the metallic element (Al) that constitutes this boehmite powder, this starting compound powder, calcium hydroxide and water are packed in the pressure vessel, keep with thermostat.Obtain desirable boehmite powder by reaction product filtration, washing, the drying that will obtain.As the maintenance temperature in the above-mentioned thermostat, as long as for generating the temperature province of reaction product, keep more suitable at (for example 180～220 ℃, for example 200 ℃ ± 10 ℃) more than 180 ℃ usually.In addition, as long as the retention time was set at up to time of reaction of formation product fully, it is just enough to be set at more than 60 hours (for example 60～100 hours, for example about 72 hours) usually.By the interpolation of calcium hydroxide, the boehmite particle is grown greatlyyer, therefore becomes to handle to adjust the circularity distribution of boehmite powder easily by pulverization process described later or spheroidizing.
In the operation that pulverization process in above-mentioned (B) or spheroidizing are handled, metal compound powders is carried out pulverization process or spheroidizing processing, so that the intermediate value in the distribution of the circularity of the above-mentioned metal compound powders that obtains becomes 0.85～0.97.
Intermediate value that the circularity of the above-mentioned metal compound powders that obtains distributes greater than 0.97 situation under, preferably metal compound powders is carried out pulverization process so that the intermediate value that circularity distributes becomes 0.85～0.97.
As the employed reducing mechanism of this pulverization process, so long as suitably being adjusted into the reducing mechanism of 0.85～0.97 scope, the intermediate value that circularity can be distributed just has no particular limits.For example, can preferably use the reducing mechanism of aeropulverizer, ball mill, vibrator etc.Wherein, use aeropulverizer can more suitably adjust aspect the circularity distribution preferred.
State in the use under the situation that aeropulverizer carries out pulverization process, the circularity of metal compound powders distributes, and can adjust by Change Example such as the pulverization conditions of blast (pulverizing air pressure) and pulverizing time etc.That is, by suitably selecting the pulverization conditions of blast (pulverizing air pressure) and pulverizing time etc., the intermediate value that can form the circularity distribution satisfies 0.85～0.97 metal compound powders.For example, preferably the blast (pulverizing air pressure) of aeropulverizer is set at about 0.2～0.4MPa.In addition, the degree that circularity distributes also depends on the time of having carried out pulverization process.The pulverizing time is preferably set to about 5～20 minutes.Pulverize by adopting based on blast and the impulsive force of the time of pulverizing of such prescribed limit, the intermediate value that can easily form the circularity distribution satisfies 0.85～0.97 metal compound powders.Moreover preferred: which condition is the circularity of adjustment metal compound powders change when distributing is suitably determined according to the reducing mechanism that uses.
Intermediate value that the circularity of the above-mentioned metal compound powders that obtains distributes less than 0.85 situation under, preferably metal compound powders is carried out spheroidizing and handles, so that the intermediate value that circularity distributes becomes 0.85～0.97.Handle employed processing unit as spheroidizing, just have no particular limits so long as the intermediate value that circularity can be distributed suitably be adjusted into the processing unit of 0.85～0.97 scope.For example, can preferably use the particle processing unit of Network リ プ ト ロ ン オ ー Block (KRYPTRON Orb) (the ア ー ス テ of Co., Ltd. Network ニ カ system), Off ァ カ Le テ ィ (FACULTY) (ホ ソ カ ワ ミ Network ロ Application Co., Ltd. system) etc.Wherein, it is preferred to use グ リ プ ト ロ ン オ ー Block can carry out at the particle diameter that does not change filler grain aspect the spheroidizing processing.
State Network リ プ ト ロ ン オ ー Block in the use and carry out under the situation that spheroidizing handles, the circularity of metal compound powders distributes and can adjust by the treatment conditions that change rotating speed and number of processes etc.That is, by suitably selecting the treatment conditions of rotating speed and number of processes etc., the intermediate value that can form the circularity distribution satisfies 0.85～0.97 metal compound powders.For example, the rotating speed of Network リ プ ト ロ ン オ ー Block is preferably set to about 6000～10000rpm.In addition, the degree that circularity distributes also depends on and has carried out the number of processes that spheroidizing is handled.Number of processes is preferably set to about 2～5 times.Handle by carry out spheroidizing under such condition, the intermediate value that can easily form the circularity distribution satisfies 0.85～0.97 metal compound powders.Moreover which condition is the circularity of preferably adjusting metal compound powders change when distributing is suitably determined according to the processing unit that uses.Above-mentioned spheroidizing is handled and also can be used aeropulverizer to carry out.Aeropulverizer also can remove the corner angle of particle by the control air quantity, improves circularity.
In the operation of the formation porous layer in above-mentioned (C), after handling intermediate value that the circularity with metal compound powders distributes and be adjusted into 0.85～0.97 scope by above-mentioned pulverization process or spheroidizing, be modulated at the porous layer that has disperseed this metal compound powders and adhesive in the solvent and form and use coating.Then, this porous layer formation is applied to the surface of separator sheets and carries out drying with coating, form porous layer thus.
Form with employed solvent in the coating as above-mentioned porous layer, can enumerate the organic system solvent of N-methyl pyrrolidone (NMP), pyrrolidones, methylethylketone, methylisobutylketone, cyclohexanone, toluene, dimethyl formamide, dimethylacetylamide etc. or their two or more combination.Perhaps, also can be water or based on the mixed solvent of water.As the solvent beyond the water that constitutes this mixed solvent, can suitably select to use one or more of the organic solvent (lower alcohol, lower ketones etc.) that can mix equably with water.The containing ratio that porous layer forms with the solvent in the coating does not limit especially, but is preferably about 30～60 quality % of coating integral body.
Moreover above-mentioned porous layer forms and uses coating, except metal compound powders (filler grain) and adhesive, can contain one or more the material that can use as required.As such examples of material, can enumerate the polymer that forms the tackifier performance function of using coating as porous layer.Polymer as tackifier performance function can preferably use for example carboxymethyl cellulose (CMC).
Such porous layer is formed the operation that is applied to the separator sheets surface with coating, and the situation of the porous layer that can possess with the general lithium secondary battery of making is in the past similarly carried out.For example, can be by using suitable apparatus for coating (gravure roll coating machine, slit coater, mould are coated with machine, comma coating machine, dip coaterd etc.), the above-mentioned porous layer formation with uniform thickness coating ormal weight on aforementioned barriers is made with coating.
Thereafter, by will be coated with suitable dry means the thing drying (be typically than the low-melting temperature of separator sheets, for example below 110 ℃, for example 30～80 ℃ carry out drying) remove porous layer and form with the solvent in the coating.Use the coating desolventizing by forming from porous layer, can form the porous layer that contains metal compound powders and adhesive.Can form porous layer on the surface of separator sheets like this.
The above-mentioned porous layer that obtains, the intermediate value of using circularity to distribute satisfy 0.85～0.97 metal compound powders (filler grain) formation.Therefore, can access the amount of filler in the unit volume of suitably keeping porous layer, and have the porous layer of the best of high mechanical strength and good ion permeability concurrently.If use such porous layer, then can make up satisfy that two-forty cyclic durability height, charge-discharge characteristic are good, the lithium secondary battery of at least one (being preferably all) among the excellent in safety.
Moreover, except using porous layer disclosed herein, can adopt material same and technology to make up lithium secondary battery.
For example, as described above, after the surface of separator sheets 40 has formed porous layer 42, can as shown in Figure 3 positive plate 10 and negative plate 20 be reeled across two pieces of separator sheets 40, make rolled electrode body 80.Then, can as shown in Figure 2 rolled electrode body 80 be accommodated in the container body 52, in this container body 52, dispose (injection) suitable nonaqueous electrolytic solution.
Nonaqueous electrolytic solution as together accommodating with above-mentioned rolled electrode body 80 in container body 52 can be not particularly limited to use the electrolyte same with the employed nonaqueous electrolytic solution of lithium ion battery in the past.This nonaqueous electrolytic solution, typical, have the composition that in suitable nonaqueous solvents, contains supporting electrolyte.As above-mentioned nonaqueous solvents, can use for example ethylene carbonate (EC), carbonic acid ethyl methyl esters (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), propylene carbonate (PC) etc.In addition, as above-mentioned supporting electrolyte, can preferably use for example LiPF 6, LiBF 4, LiAsF 6, LiCF 3SO 3, LiClO 4Deng lithium salts.For example, can preferably use and contain in the mixed solvent of EC, EMC and DMC concentration with about 1 mol in the volume ratio by 3:4:3 and contain LiPF as supporting electrolyte 6Nonaqueous electrolytic solution.
By above-mentioned nonaqueous electrolytic solution and rolled electrode body 80 are together accommodated in the container body 52, and with the peristome of lid 54 airtight container main bodys 52, finish the structure (assembling) of the lithium ion battery 100 of present embodiment.Moreover the packaging technology of container body 52 and the configuration of electrolyte (fluid injection) technology can similarly be carried out with the method for implementing in the manufacturing of in the past lithium ion battery.Carry out the adjustment (initial charge/discharge) of this battery thereafter.Also can outgas as required and the operation of quality inspection etc.
Below, test example related to the present invention is described, but is not that intention limits the invention to the content shown in the following test example.
The making of＜filler grain＞
In embodiment 1, produce boehmite powder as filler grain.At first, to drop in the pressure vessel as alumina trihydrate 100g and the water 150g of initiation material, after having added calcium hydroxide 17mg, in 200 ℃ thermostat, kept 72 hours, thereby with the reaction product filtration, washing, the dry boehmite that synthesized that obtain.Then, the boehmite synthetic that obtains is dropped in the aeropulverizer (ホ ソ カ ワ ミ Network ロ Application Co., Ltd. system, model 100AFG), pulverize with the blast of 0.3MPa and produced boehmite powder in 15 minutes thus.The intermediate value that the circularity of the boehmite powder that obtains distributes is 0.85, and following value is 0.7.Moreover the intermediate value that circularity distributes and following value are to use flow-type particle image analytical equipment (シ ス メ ッ Network ス Co., Ltd. system, model FPIA-3000 take population and be about 2000) to calculate.
In embodiment 2, commercially available titania powder (Kanto Kagaku K. K.'s system) is dropped in the aeropulverizer, pulverize under the conditions shown in Table 1 and produce titania powder thus.The intermediate value that the circularity of the titania powder that obtains distributes is 0.89, and following value is 0.73.Moreover the intermediate value that the circularity of the titania powder before pulverizing distributes is about 0.985.
In embodiment 3～6, produce alumina powder as filler grain.At first, thus will in air atmosphere, under 1050 ℃, burn till as the aluminium hydroxide of initiation material and synthesize Alpha-alumina in 96 hours.Then, the aluminium oxide synthetic that obtains is dropped in the aeropulverizer, pulverize under the conditions shown in Table 1 and produce alumina powder thus.Press the order of embodiment 3～6, the intermediate value that the circularity of resulting alumina powder distributes is 0.91,0.93,0.95,0.96, and following value is 0.82,0.85,0.88,0.89.
In embodiment 7, commercially available magnesium hydroxide powder (Kanto Kagaku K. K.'s system) is dropped in the aeropulverizer, pulverize under the conditions shown in Table 1 and produce magnesium hydroxide powder thus.The intermediate value that the circularity of the magnesium hydroxide powder that obtains distributes is 0.965, and following value is 0.9.Moreover the intermediate value that the circularity of the magnesium hydroxide powder before pulverizing distributes is about 0.84.
In embodiment 8, commercially available magnesium carbonate powder (Kanto Kagaku K. K.'s system) is dropped in the aeropulverizer, pulverize under the conditions shown in Table 1 and produce the magnesium carbonate powder thus.The intermediate value that the circularity of the magnesium carbonate powder that obtains distributes is 0.97, and following value is 0.91.Moreover the intermediate value that the circularity of the magnesium carbonate powder before pulverizing distributes is about 0.98.
In comparative example 1, operation similarly to Example 2, thus but will adopt the pulverizing condition shown in the table 1 that changes to of aeropulverizer to produce titania powder.The intermediate value that the circularity of the titania powder that obtains distributes is 0.8, and following value is 0.68.
In comparative example 2, similarly operate with embodiment 3～6, thereby but will adopt the pulverizing condition shown in the table 1 that changes to of aeropulverizer to produce alumina powder.The intermediate value that the circularity of the alumina powder that obtains distributes is 0.82, and following value is 0.66.
In comparative example 3, commercially available titania powder (Kanto Kagaku K. K.'s system) is dropped into Network リ プ ト ロ ン オ ー Block (the ア ー ス テ of Co., Ltd. Network ニ カ system, model C SH0) in, produces titania powder thus 3 times with the rotating speed processing of 8000rpm.The intermediate value that the circularity of the titania powder that obtains distributes is 0.98, and following value is 0.92.
In comparative example 4, commercially available alumina powder (Kanto Kagaku K. K.'s system) is dropped in the Network リ プ ト ロ ン オ ー Block, handle under the conditions shown in Table 1 and produce alumina powder thus.The intermediate value that the circularity of the alumina powder that obtains distributes is 0.983, and following value is 0.92.
Figure BDA00002840452800171
The formation of＜porous layer＞
With above-mentioned various metal compound powders (filler grain) and the acrylic adhesive that obtains, becoming the mode that 97.4:2.6 and solid constituent ratio become 40 quality % with metal compound powders and the mass ratio of adhesive mixes in NMP, the modulation porous layer forms uses coating, it in single face coating of the separator sheets 40 of long shape and carry out drying, has been formed porous layer 42 thus.Porous layer forms with the coating weight of coating and regulates feasible about 0.7mg/cm that becomes 2(solid constituent benchmark).As drying condition, the atmosphere temperature in the hot-air drying stove is set at 80 ℃, wind speed is set at 16.2m/s.Moreover, as shown in table 1 in this example, as separator sheets, used these two kinds of the single layer structure of polyethylene (PE) and polypropylene-polyethylene-polypropylene (PP/PE/PE) three-deckers.Any separator sheets all is set at the thickness of 20 μ m, 47% porosity.
Calculate the porosity of the above-mentioned various porous layers that obtain.The porosity of porous layer (%) is calculated by (1-W/ ρ V) * 100.At this, W is the quality of porous layer, determines by electronic balance.V is the apparent volume of porous layer, calculates by the external dimensions (thickness * area) that adopts the observable porous layer of SEM.ρ is the real density (solid density) that constitutes the material of porous layer.Show the result in table 1.
Can be clear and definite from the result of table 1, the intermediate value that circularity is distributed is set at the porous layer of 0.85～0.97 embodiment 1～8, and porosity becomes 51～70%, and is more suitable as porous layer.Particularly be set at 0.85～0.91 by the intermediate value that circularity is distributed, can be made for height of level and have realized 60～70% electrolyte permeability and the porous layer of mechanical strength.According to this result, from the electrolyte permeability of raising porous layer and the viewpoint of mechanical strength, the intermediate value that the circular degree distributes is 0.85～0.91.
The mensuration of＜film resistor＞
Use the separator sheets structure mensuration that has various porous layers of above-mentioned making to use element cell, estimated its film resistor (Rs).Specifically, as the expression of Fig. 5 pattern ground, make porous layer 42 and separator sheets 40 infiltration nonaqueous electrolytic solutions, it is clipped in area is 35mm 2, thickness is 62 of two pieces of copper coins of 1mm.As nonaqueous electrolytic solution, use and to contain in the mixed solvent of ethylene carbonate (EC), dimethyl carbonate (DMC) and carbonic acid ethyl methyl esters (EMC) concentration with about 1 mol in the volume ratio by 3:4:3 and contain LiPF as supporting electrolyte 6Nonaqueous electrolytic solution.Be that 1 piece, 2 pieces, 3 pieces mode is made such element cell 60 respectively with separator sheets.Then, each element cell is put into 25 ℃ thermostat, on one side from the moment of torsion pressure that applies 50cNm up and down of two pieces of copper coins 62, adopt AC impedence method on one side, measured the resistance value (Rs) of element cell.For the condition determination of AC impedance, interchange applied voltage is set at 5mV, frequency range is set at 10000Hz～1Hz.The resistance value of each element cell of obtaining is drawn with respect to piece number of dividing plate, carry out linear approximation (linear approximation: linearly approximated), obtain the film resistor of per 1 piece of dividing plate.Show the result in table 1.
Can be clear and definite from the result of table 1, the intermediate value that circularity distributes is the element cell of 0.85～0.97 embodiment 1～8, compares with comparative example 3,4 element cell, film resistor reduces significantly.Particularly be set at below 0.91 by the intermediate value that circularity is distributed, can realize 1.5 Ω cm 2Following extremely low film resistor.In addition, the following value that circularity is distributed is set at the element cell of 0.7～0.9 embodiment 1～7, compares with the element cell of embodiment 8, and film resistor further reduces.
The evaluation of＜battery behavior＞
Use the above-mentioned separator sheets that has various porous layers that obtains to make up lithium secondary battery, estimated its battery behavior.Lithium secondary battery is made as follows.
＜positive plate＞
Will be as the Li of positive active material 1.15Ni 0.33Mn 0.33Co 0.33O 2Powder, as the acetylene black (AB) of electric conducting material with as the polyvinylidene fluoride (PVdF) of adhesive, the mode that becomes 88:10:2 with the mass ratio of these materials is mixed in N-methyl pyrrolidone (NMP), modulates positive electrode active material layer with sticking with paste.By this positive electrode active material layer is become band and carries out drying with sticking with paste two sided coatings at the aluminium foil (positive electrode collector 12) of lengthy motion picture shape, produce the positive plate 10 that is provided with positive electrode active material layer 14 on the two sides of positive electrode collector 12.Positive electrode active material layer has carried out adjusting so that the two sides becomes about 17.2mg/cm altogether with the coating weight of sticking with paste 2(solid constituent benchmark).
＜negative plate＞
Will be as the powdered graphite of negative electrode active material, as the styrene butadiene rubbers (SBR) of adhesive with as the carboxymethyl cellulose (CMC) of tackifier, the mode that becomes 98.6:0.7:0.7 with the mass ratio of these materials is disperseed in water, modulates negative electrode active material layer with sticking with paste.This negative electrode active material layer with the two sided coatings of sticking with paste at the Copper Foil (negative electrode collector 22) of lengthy motion picture shape, is produced the negative plate 20 that is provided with negative electrode active material layer 24 on the two sides of negative electrode collector 22.Negative electrode active material layer has carried out adjusting so that the two sides becomes about 11.1mg/cm altogether with the coating weight of sticking with paste 2(solid constituent benchmark).
＜lithium secondary battery＞
By positive plate 10 and negative plate 20 are reeled to produce rolled electrode body 80 across two pieces of separator sheets 40 that have porous layer.It is relative with positive plate to be configured to porous layer when at this moment, separator sheets is for PE.It is relative with negative plate to be configured to porous layer when in addition, separator sheets is for PP/PE/PP.The rolled electrode body that obtains like this 80 and nonaqueous electrolytic solution are together accommodated battery case 50(18650 type cylinder type) in, the peristome of battery case 50 is hermetic sealed.As nonaqueous electrolytic solution, use and to contain in the mixed solvent of ethylene carbonate (EC), carbonic acid ethyl methyl esters (EMC) and dimethyl carbonate (DMC) concentration with about 1 mol in the volume ratio by 3:4:3 and contain LiPF as supporting electrolyte 6Nonaqueous electrolytic solution.Assemble out lithium secondary battery 100 like this.
The endurance test of＜two-forty＞
To the above-mentioned lithium secondary battery that obtains each, give the charge and discharge mode of the CC discharge of under 20C, carrying out for 10 seconds repeatedly, carried out the charge and discharge cycles test.Specifically, under room temperature (about 25 ℃) environment, will carry out the CC discharge in 10 seconds with 20C, and after 5 seconds of stopping, carry out the charge and discharge cycles of the CC charging in 40 seconds with 5C and carry out repeatedly 10000 times continuously.Then, the IV resistance (initial resistance of lithium secondary battery) before the test of above-mentioned charge and discharge cycles and the IV resistance after the charge and discharge cycles test are calculated the resistance increment rate.At this, the IV resistance before and after the charge and discharge cycles, the voltage drop of discharge after 10 seconds when carrying out pulsed discharge under 25 ℃, 30C calculated respectively.Moreover resistance increment rate (%) is tried to achieve by [the IV resistance before (the IV resistance before the IV resistance after the charge and discharge cycles test-charge and discharge cycles test)/charge and discharge cycles test] * 100.Show the result in table 1.
The test of＜foreign matter internal short-circuit＞
In addition, adopt the method structure lithium secondary battery same with above-mentioned steps, implemented the test of foreign matter internal short-circuit.The test of foreign matter internal short-circuit, being to use height 0.2mm * width 0.1mm and each limit is the nickel small pieces of the L font of 1mm, carries out based on JISC8714, to such an extent as to investigated the defective products (NG product) that has or not smolder (smoking).Show the result in table 1.To confirm not that in table 1 battery of smoldering represents with zero, confirm that the battery of smoldering is with * expression.
As shown in table 1, the intermediate value that circularity is distributed is set at and is lower than 0.85 or be higher than the battery of the comparative example 1～4 of 0.97 value, and the resistance increment rate after the test of two-forty charge and discharge cycles increases significantly.In addition, comparative example 1,2 battery are confirmed to smolder in the test of foreign matter internal short-circuit.Relative therewith, the intermediate value that circularity is distributed is set at the battery of 0.85～0.97 embodiment 1～8, and the resistance increment rate after the cyclic test is 13% below, for well.In addition, do not confirm to smolder in the test of foreign matter internal short-circuit yet, can be confirmed to be the battery of excellent in safety.That is, be set at 0.85～0.97 by the intermediate value that circularity is distributed, can be made for the battery that satisfies two-forty charge and discharge cycles durability and fail safe with height of level.According to this result, from the viewpoint of two-forty charge and discharge cycles durability and fail safe, the intermediate value that the circular degree distributes is set at 0.85～0.97.In addition, be under this situation for the battery of test, be set at 0.7～0.9 by the following value that circularity is distributed, the resistance increment rate is below 12%, further improved (embodiment 1～7), particularly be set at 0.85～0.93 by the intermediate value that circularity is distributed, can realize this extremely low resistance increment rate (embodiment 1～4) below 8%.
From above result, according to this test, be set at 0.85～0.97 by the intermediate value that circularity is distributed, can realize the lithium secondary battery of the little and excellent in safety of resistance increment rate after the two-forty charge and discharge cycles.Therefore, according to this formation, can provide the high performance lithium secondary battery of two-forty charge and discharge cycles durability and excellent in safety.
More than, by the present invention preferred embodiment has been described, but such record and non-limiting item can be carried out various changes certainly.
For example, in above-mentioned execution mode and test example, situation on the face relative with negative plate 20 that shows that porous layer 42 is formed at separator sheets 40, but be not limited to this, also can be formed on the face relative with positive plate (the perhaps two sides of separator sheets) of separator sheets.In addition, be not limited to the surface of separator sheets, also can form on the surface of positive plate or negative plate.
In addition, have in employing under the limit of porous layer of the filler grain that satisfies the intermediate value that preferred circularity disclosed herein distributes, the shape of constructed lithium secondary battery (profile and size) is not particularly limited.Outer dress can be slim type with formations such as laminated films, also can be that the battery external shell is the battery of drum or rectangular shape, perhaps also can be small-sized button shape.
Moreover any lithium secondary battery 100 disclosed herein is to possess the performance (for example can obtain high-output power) that is suitable as the battery that vehicle carries, particularly the battery of the excellent in te pins of durability that discharges and recharges for two-forty.Therefore, according to the present invention, as shown in Figure 6, can provide the vehicle 1 that possesses any lithium secondary battery 100 disclosed herein.Particularly can provide and possess this lithium secondary battery 100 as the vehicle 1(of power source (being typically the power source of motor vehicle driven by mixed power or motor vehicle) automobile for example).
In addition, as the preferred application of technology disclosed herein, but illustration: and imagination can comprise more than the 50A (50A～250A) the and then be (lithium secondary battery that uses under the charge and discharge cycles of the high rate discharge of 100A～200A) for example more than the 100A for example; Imagination can comprise that theoretical capacity is the big volume type of (and then for more than 3Ah) and (10C～50C) the and then be (lithium secondary battery that uses under the charge and discharge cycles that the two-forty of 20C～40C) discharges and recharges for example more than the 20C for example 10C more than more than the 1Ah; Etc..
Utilize possibility on the industry
According to formation of the present invention, can provide a kind of high performance nonaqueous electrolytic solution secondary battery of two-forty excellent in te pins of durability.

Claims (6)

1. a nonaqueous electrolytic solution secondary battery is the nonaqueous electrolytic solution secondary battery that possesses electrode body, and described electrode body is that positive plate and negative plate overlap the electrode body that forms across separator sheets,
Between at least one side and described separator sheets of described positive plate and described negative plate, be formed with the porous layer with filler grain and adhesive,
Intermediate value during the circularity of the filler grain that contains in the described porous layer distributes is 0.85～0.97.
2. nonaqueous electrolytic solution secondary battery according to claim 1 in the circularity of described filler grain distributes, and is 0.7～0.9 from the suitable circularity value of the accumulation 10% of the little side of circularity.
3. nonaqueous electrolytic solution secondary battery according to claim 1 and 2, described filler grain is aluminium oxide or hydrated alumina.
4. according to each described nonaqueous electrolytic solution secondary battery of claim 1～3, described porous layer is formed at the surface of described separator sheets at least.
5. nonaqueous electrolytic solution secondary battery according to claim 4, described porous layer is formed on the face relative with negative plate of described separator sheets.
6. according to each described nonaqueous electrolytic solution secondary battery of claim 1～5, described electrode body is the rolled electrode body that described positive plate and described negative plate are reeled and formed across described separator sheets.
CN201080068629.XA 2010-08-19 2010-08-19 Non-aqueous electrolyte secondary battery Active CN103201878B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2010/064032 WO2012023199A1 (en) 2010-08-19 2010-08-19 Non-aqueous electrolyte secondary battery

Publications (2)

Publication Number Publication Date
CN103201878A true CN103201878A (en) 2013-07-10
CN103201878B CN103201878B (en) 2015-06-24

Family

ID=45604873

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201080068629.XA Active CN103201878B (en) 2010-08-19 2010-08-19 Non-aqueous electrolyte secondary battery

Country Status (4)

Country Link
US (1) US9583769B2 (en)
JP (1) JP5574196B2 (en)
CN (1) CN103201878B (en)
WO (1) WO2012023199A1 (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5614597B2 (en) * 2012-04-10 2014-10-29 トヨタ自動車株式会社 Nonaqueous electrolyte secondary battery
WO2013187458A1 (en) * 2012-06-12 2013-12-19 三菱製紙株式会社 Separator for lithium ion cell
KR102107364B1 (en) 2012-06-29 2020-05-07 미쯔비시 케미컬 주식회사 Laminated porous film, separator for non-aqueous electrolyte secondary battery, and non-aqueous electrolyte secondary battery
JP6266454B2 (en) * 2013-07-18 2018-01-24 三菱製紙株式会社 Manufacturing method of battery separator
US20150380708A1 (en) * 2014-01-07 2015-12-31 Mitsubishi Plastics, Inc. Multilayer porous film, separator for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery
JP6002353B1 (en) 2014-12-10 2016-10-05 三菱樹脂株式会社 Alumina slurry
JP6203910B2 (en) * 2016-06-28 2017-09-27 住友化学株式会社 Insulating porous layer for non-aqueous electrolyte secondary battery and laminated separator for non-aqueous electrolyte secondary battery
JP6614202B2 (en) * 2017-06-01 2019-12-04 日亜化学工業株式会社 Cathode active material for non-aqueous electrolyte secondary battery and method for producing the same

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005071978A (en) * 2003-08-06 2005-03-17 Mitsubishi Chemicals Corp Separator for nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery using it
US20090053609A1 (en) * 2007-08-22 2009-02-26 Sanyo Electric Co., Ltd. Non-aqueous electrolyte battery
CN101567434A (en) * 2009-06-04 2009-10-28 复旦大学 Lithium-ion membrane and the application thereof
CN101809783A (en) * 2007-09-27 2010-08-18 三洋电机株式会社 Separator for nonaqueous electrolyte battery and nonaqueous electrolyte battery

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09237622A (en) * 1996-02-29 1997-09-09 Nissan Motor Co Ltd Organic battery
JP2002265657A (en) * 2001-03-15 2002-09-18 Nitto Denko Corp Polyolefin porous sheet and method for producing the same
KR101105748B1 (en) * 2005-12-08 2012-01-17 히다치 막셀 가부시키가이샤 Separator for electrochemical device and method for producing same, and electrochemical device and method for manufacturing same
JP5213007B2 (en) * 2007-02-23 2013-06-19 日立マクセル株式会社 Battery separator and non-aqueous electrolyte battery
JP2008226566A (en) * 2007-03-12 2008-09-25 Hitachi Maxell Ltd Composition for porous insulating layer formation, positive electrode for lithium-ion secondary battery, negative electrode for lithium ion secondary battery, and lithium-ion secondary battery
JP5219621B2 (en) * 2007-08-22 2013-06-26 三洋電機株式会社 Non-aqueous electrolyte battery
JP5603543B2 (en) * 2008-07-07 2014-10-08 日立マクセル株式会社 Battery separator and non-aqueous electrolyte battery
KR101562276B1 (en) * 2008-09-12 2015-10-21 니혼바이린 가부시기가이샤 Separator for lithium ion secondary battery, method for manufacture thereof, and lithium ion secondary battery
JP5370289B2 (en) * 2010-06-30 2013-12-18 日本ゼオン株式会社 Non-aqueous battery separator and non-aqueous battery using the same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005071978A (en) * 2003-08-06 2005-03-17 Mitsubishi Chemicals Corp Separator for nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery using it
US20090053609A1 (en) * 2007-08-22 2009-02-26 Sanyo Electric Co., Ltd. Non-aqueous electrolyte battery
CN101809783A (en) * 2007-09-27 2010-08-18 三洋电机株式会社 Separator for nonaqueous electrolyte battery and nonaqueous electrolyte battery
CN101567434A (en) * 2009-06-04 2009-10-28 复旦大学 Lithium-ion membrane and the application thereof

Also Published As

Publication number Publication date
JP5574196B2 (en) 2014-08-20
JPWO2012023199A1 (en) 2013-10-28
US20130143091A1 (en) 2013-06-06
CN103201878B (en) 2015-06-24
US9583769B2 (en) 2017-02-28
WO2012023199A1 (en) 2012-02-23

Similar Documents

Publication Publication Date Title
CN103155215B (en) Lithium Secondary Battery Of Nonaqueous Electrolyte
CN102549813B (en) Lithium secondary battery and manufacturing method therefor
CN103201878B (en) Non-aqueous electrolyte secondary battery
JP6275822B2 (en) Non-aqueous electrolyte battery active material, non-aqueous electrolyte battery electrode, non-aqueous electrolyte secondary battery, battery pack, and method for producing non-aqueous electrolyte battery active material
Armstrong et al. TiO2 (B) nanowires as an improved anode material for lithium-ion batteries containing LiFePO4 or LiNi0. 5Mn1. 5O4 cathodes and a polymer electrolyte
CN110165284B (en) Lithium ion secondary battery
CN103370810B (en) Secondary cell and battery pack
CN102405552B (en) Lithium secondary battery and manufacture method thereof
WO2013073011A1 (en) Non-aqueous electrolyte type secondary battery
JP5487676B2 (en) Electrochemical device comprising an active material, an electrode including the active material, and an electrolyte solution including the electrode and a lithium salt
US9172083B2 (en) Lithium ion secondary battery
CN102939675B (en) Nonaqueous electrolytic solution secondary battery
CN103597638B (en) Lithium rechargeable battery
CN103718335B (en) Rechargeable nonaqueous electrolytic battery
JP2016062860A (en) Electrode active material for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery including the same
CN103250272A (en) Non-aqueous electrolyte secondary battery
CN101436679A (en) Non-aqueous electrolyte battery
KR20120061952A (en) Lithium secondary battery and positive electrode for said battery
JP4168402B2 (en) Positive electrode active material for lithium secondary battery, method for producing the same, and non-aqueous lithium secondary battery
US20230261201A1 (en) Electrochemical apparatus and electronic apparatus
TW560099B (en) Non-aqueous electrolyte secondary battery
CN105680006B (en) Active materials for non-aqueous electrolyte battery, electrode for non-queous electrolytic cells, non-aqueous electrolyte secondary battery and battery pack
TWI387144B (en) Polymer electrolyte secondary battery
JP5564872B2 (en) Nonaqueous electrolyte secondary battery
JP2007103198A (en) Anode and battery

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant